diff options
Diffstat (limited to 'nbd/nbd-internal.h')
| -rw-r--r-- | nbd/nbd-internal.h | 33 |
1 files changed, 24 insertions, 9 deletions
diff --git a/nbd/nbd-internal.h b/nbd/nbd-internal.h index 396ddb4d3e..03549e3f39 100644 --- a/nbd/nbd-internal.h +++ b/nbd/nbd-internal.h @@ -77,21 +77,36 @@ #define NBD_ESHUTDOWN 108 /* nbd_read_eof - * Tries to read @size bytes from @ioc. Returns number of bytes actually read. - * May return a value >= 0 and < size only on EOF, i.e. when iteratively called - * qio_channel_readv() returns 0. So, there is no need to call nbd_read_eof - * iteratively. + * Tries to read @size bytes from @ioc. + * Returns 1 on success + * 0 on eof, when no data was read (errp is not set) + * negative errno on failure (errp is set) */ -static inline ssize_t nbd_read_eof(QIOChannel *ioc, void *buffer, size_t size, - Error **errp) +static inline int nbd_read_eof(QIOChannel *ioc, void *buffer, size_t size, + Error **errp) { struct iovec iov = { .iov_base = buffer, .iov_len = size }; + ssize_t ret; + /* Sockets are kept in blocking mode in the negotiation phase. After * that, a non-readable socket simply means that another thread stole * our request/reply. Synchronization is done with recv_coroutine, so * that this is coroutine-safe. */ - return nbd_rwv(ioc, &iov, 1, size, true, errp); + + assert(size); + + ret = nbd_rwv(ioc, &iov, 1, size, true, errp); + if (ret <= 0) { + return ret; + } + + if (ret != size) { + error_setg(errp, "End of file"); + return -EINVAL; + } + + return 1; } /* nbd_read @@ -100,9 +115,9 @@ static inline ssize_t nbd_read_eof(QIOChannel *ioc, void *buffer, size_t size, static inline int nbd_read(QIOChannel *ioc, void *buffer, size_t size, Error **errp) { - ssize_t ret = nbd_read_eof(ioc, buffer, size, errp); + int ret = nbd_read_eof(ioc, buffer, size, errp); - if (ret >= 0 && ret != size) { + if (ret == 0) { ret = -EINVAL; error_setg(errp, "End of file"); } |